Blood Is Thicker Than Water
by xRae Asakurax
Summary: Sometimes it takes a lot more than words to make someone see their value. One turtle finds he isn't a blood brother to his related siblings. Character death, split one-shot. Non-t'cest.
1. Blood Brothers

**Rae:** I can blame this bunny solely on my beta's head. I just stupidly accepted it and wrote it. xDD

I cannot _tell_ you how hard this was to write. Not so much this bit, though Donnie going loco was a bit difficult, but the ending. AUGH, the ending! I hate finishing fics. Just thought I'd tell you. xDD Anyway, enjoy it! I warn you now, you'll need tissues~

TMNT belongs to Eastman and Laird, not to me!

* * *

"It was just a simple question!" Michelangelo glared at his red-clad brother, rubbing at the back of his head where the elder had placed a none-too-gentle smack. "You can't tell me you haven't wondered yourself!"

"No," agreed Raphael, moving smoothly into another kata as though he hadn't stopped to hit his younger sibling, "I can't. I _can_ however ask at a more appropriate time. Like maybe when we ain't in training."

"It is an interesting thought," admitted Donatello, balancing delicately on one foot while his other leg moved in ways Raph was sure weren't physically possible. "I must confess I've often thought a lot about it, and I'd be interested to find out but I never wanted to put undue pressure on you guys." He shrugged and hopped onto the other foot to repeat his previous motions on the one he had been standing on, purple bandana trails following his actions lazily. "I'm perfectly happy not knowing, if I'm honest. I merely wish to satisfy a small curiosity on my part."

"It doesn't matter if we are or aren't." Leonardo lowered nearly to the floor in a kata, stretching himself out as far as his body could reach. "We're brothers and family by bond, not blood. I mean, it's not like Master Splinter is our real father, but we see him as such regardless. Right?"

Both Raph and Don made a noise of content agreement in reply, but Mikey's expression made it clear he wasn't going to let the issue die down. However, for the remainder of the training session he seemed happy to let it drop and turn to his other favourite pastime: annoying Raph.

By the end of the training session Don was feeling a bit worn down but good; it was a healthy tiredness. He settled down at his desk and pulled the hard drive he'd been tinkering with earlier back towards him, losing himself quickly in the rewiring and mods he had planned for this little beauty.

So he really shouldn't've been surprised to gradually drag himself back to reality for a coffee refill to find the family's dubbed 'youngest' turtle's face inches from his own, blue eyes boring into his own honey ones, but he was. And he promptly fell out his chair with a yelp.

Mikey blinked and then helped the genius back up again with a rushed apology. "I'm sorry bro, you were totally spaced!"

"You should know better than to scare me like that while I'm working, Mikey." There was no anger or harshness in Don's voice, just the faint tint of recovery from a shock and a resigned kind of reprimanding tone. "Now, what is it? I need some coffee, walk with me."

The orange-banded turtle followed Don into the kitchen and watched him take the coffee down to spoon two teaspoons into his cup and add sugar before clicking the kettle on. "I'm just wondering if you can actually do a DNA comparison with all your techy geeky stuff," said Mikey, airily.

Don turned to face his brother, shifting his weight onto one hip, crossing his arms and raising an eyeridge. "You're just not gonna leave it alone, are you?"

"Nope."

Don weighed his options briefly. It wasn't the tech that was the problem, it was the effects the results could have if they weren't what everyone wanted to hear. Then again, it was just like Leo said; they were brothers by bond, not blood. They had spent their lives so far not actually knowing if they were physically related or not, so confirming it shouldn't make a difference. Right?

Don ran a hand down his face, his brain going through every single pro and con and placing them against each other, judging them accordingly. He poured some boiling water into his mug, stirring the contents slowly, thoughtfully. Finally, he came to decision.

"Alright," he said wearily, "I'll do it. _But_-" he raised a hand to forestall any forthcoming celebrations from Mikey, "-only if Raph and Leo want to as well _and_ only if Master Splinter gives his permission. If any of them say no, I won't do it."

Mikey made a face and opened his mouth like he was going to protest, but then snapped his beak shut and nodded. "Fair enough," he conceded.

Don made a satisfied noise and vanished out the kitchen door back to his lab, steaming prize clutched tightly in one hand. Mikey watched him go, blue eyes bright and an excited fluttering in his stomach.

-x-

"Sensei, wait." Donatello's voice stopped every turtle in their tracks from leaving their training session the next day, and Splinter himself turned back in slight surprise.

"Yes, my son, what is it?"

Don glanced quickly at the others and motioned them back. They trotted up to their genius brother obediently, sitting down and waiting. "I wanted to ask your permission for something, and see what my brothers had to say on the issue." He sat down as well, lowering himself to his knees and taking a deep breath. "Michelangelo recently brought up the... point about whether we were blood brothers or not. He cornered me yesterday evening, requesting I perform a DNA test. I told him I would only do it if both Raph and Leo wanted to, and you gave your consent."

Splinter frowned as Raph and Leo exchanged glances behind Don. "Are you sure this is a wise course of action, my son?"

Don shook his head. "No, sensei. That's why I wished to discuss it as a family."

Splinter bowed his head and leaned on his walking stick. "What are your thoughts then, Donatello?"

"I'm not sure it's a good idea," he said simply. "I'm worried about the repercussions knowing the results could have."

"Repercussions?" Leo spoke up for the first time.

"Yeah." A sigh. "I'm afraid it'll drift us apart if we find out we're actually not related, or only two of us are, or if all four of us are but only to one other Turtle. I'm also concerned that I may find some kind of genetic defects or unknown factors that could have a huge impact on us. It's risky playing around with DNA."

"Somehow," said Leo calmly, the hint of a proud smile on his face, "I don't think the drifting is going to be a problem. We're too close for something like that to come between us."

"I agree." Raph folded his arms across his plastron. "That ain't something that's gonna factor in, Brainiac, I can tell you that now."

"You don't know that!" Don whirled to face them, then clenched his fist to calm the sudden surge of upset. "You just don't know that..." He felt a hand on his shoulder, and he raised honey eyes to see Mikey looking at him encouragingly. Splinter cleared his throat, and the four turtles brought their attentions back to him.

"I would not stop my sons from making their own decisions and possible victories or mistakes, but I implore you to think carefully about it. Donatello is right, you might not realize how much of an impact it may have." He inclined his head. "You have my permission. But please, be careful." The master flicked his tail, gave his sons a last once-over and then continued on to his room. Silence reigned for a couple of minutes.

"I still think we should know," said Mikey, uncommonly quietly. Don made a small keening noise in the back of his throat, refusing to look up at any of the others, and Leo gathered him into a rare hug. Don offered no resistance, and after a couple minutes he sighed.

"I'll do it if you guys want me to. I know I'm curious, I'm just..." he trailed off into Leo's chest, and then escaped from the embrace. "So?"

Leo looked around at Raph, who scrunched his beak up slightly and nodded, and Mikey, who just grinned and leaned back. He brought his gaze back to Don, and then bobbed his head himself. "I think we're in agreement, then. Let's find out."

The genius turtle stood up, quirked a half-smile at his brothers and walked off to his lab with the instructions to "stay there a minute". A couple minutes later Don returned with four cotton swabs and four test-tubes, which he set down on a small mat. He kept one cotton swab and one tube in his hand, though, and turned to Leo first, asking him to hold the glass cylinder. The blue-banded turtle did as asked, and Don tapped his beak to make him open his mouth. A couple swipes of the puffball across the inside of one cheek and he was putting it carefully into the test-tube, which he sealed and wrote 'LEO' on in capital letters with permanent marker.

Michelangelo clutched the tube that was shoved into his hands, and he opened his mouth without a word before Don asked. The cottonball brushed his left cheek twice and was dropped unceremoniously into the test-tube. 'MIKEY' was scrawled haphazardly and vertically across it.

Raph did exactly the same thing to exactly the same procedure, and his name marked the test-tube his cottonball resided in. Don then uncapped the final tube, swabbed his own cheek and put his safely away where it belonged.

That done the bo-staff wielder gathered up all four tubes carefully in his hands. "They'll take a while to be processed seeing as my equipment for this is hardly top-of-the-line, so don't expect them immediately," he said lightly, giving them a tiny smile and vanishing.

His brothers merely exchanged glances and shrugged.

-x-

"I've decided to use Leo's DNA as the comparative," said Don, waving a piece of paper with a line of black bar splodges on it at the other three turtles. "It seemed about the most logical choice." He propped it up on the easel he'd borrowed from Mikey, then snatched up another three sheets of paper. "These are ours," he said. "I haven't looked at them, so I have no idea what they're like." Each paper was marked with their corresponding names, and Don picked Mikey's out first.

"Moment of truth!" exclaimed the orange-clad turtle, bouncing slightly on his heels. Leo rolled his eyes and poked their youngest sibling.

"Somehow, I'm hoping I'm not related to you so I know craziness isn't hereditary," the katana-wielder teased. Mikey pouted at him after a cry of, "oi!". Don cleared his throat, drawing their attention once more, and pointed at the easel with an amused smile.

Half of Mikey's black bars matched Leo's perfectly.

Both of them gaped at the results, and then suddenly Leo was knocked to the floor by a happily squealing green-and-orange blur who hugged him fiercely. It was returned whole-heartedly, making Don grin.

"Now for Raph," he announced, picking up Raph's piece of paper. The sai user straightened, fingers twitching as it was turned and placed in between Mikey's and Leo's.

Once again, half the bars matched up to Leonardo's and half matched up with Michelangelo's.

"Alright!" Raph pumped a fist in the air, turning on Mikey and noogieing him thoroughly to squeals of protesting delight.

"And now my turn." Don's stomach did a little flip-flop as he raised his own paper. His brothers stilled and looked back in anticipation as the final print-out was turned around and placed between Mikey and Raph's.

Don stared, hiccuped slightly, and he felt a little sick. Raph made an odd noise, followed by Leo who voiced a sympathetic groan.

Mikey simply walked up to the genius and hugged him tightly.

None of Don's DNA bars matched any of the other turtles'. He wasn't related to any of them in any way.

That sinking in, he suddenly burst out of Mikey's grip and wordlessly fled to his room. The other three heard the latches being done up, a dull clunking resounding around a suddenly silent lair, locking all of them out. Raph made a move to go after the younger turtle, but Leo grabbed his arm gently and shook his head.

"No, Raph. I think Don needs a little time alone."

"This..." Mikey took Don's result paper off the easel and began scrutinizing it and comparing it, perhaps hoping that for once Don had made a mistake.

"Is exactly what Don meant when he said it could affect us," finished Leo.

"He ain't family by blood, but it's like ya said earlier Leo; we're brothers by bond." Raph pinched at his brow and exhaled noisily. "Now what?"

"We make sure he knows that," replied Leo quietly. "But for now just leave him. He'll come to us when he's ready."

-x-

"Good morning, Don!" Mikey skipped into the kitchen with a cheery voice, which caused the turtle lost in his thoughts at the table to start out of his reverie with a jump and a couple choice swear words as he spilt coffee all over the tabletop.

"Dammit Mike, don't scare me like that!" Don grabbed several sheets of kitchen towel and started dabbing at the mess, shooting the nunchuck-user an annoyed glare. "That's the second time you've done that to me in the space of about as many days!"

"Not my fault you zone out too much." Mikey attempted a tease which would normally get a sheepish grin, an absent scratch at the back of the head and some smart-alec comment back. But all he got this time was a deepened glare before the damp towels were binned, the coffee mug tossed in the sink and Don himself stalking out the room very swiftly and very curtly.

Mikey stared at the door in surprise, canting his head. A worried expression settled briefly, before deciding that even geniuses have weird days and chalking it up to a mood.

-x-

It wasn't just Mikey out to get him, Don decided. His moodiness carried over the next few days, sparking several fights with Raph and biting rebuttals towards Leo. The latter was simply worried about his brother, but getting increasingly frustrated and persistent when Don refused time and again to talk to him.

Raph needed his brainiac brother back, simply because he missed their usual sessions of hanging in the garage tinkering with things and just talking. They had barely got ten words out of the bojutsu turtle, and while he didn't really show it he was getting antsy and concerned for Don. It resulted in his inability to express his feelings properly causing a lot of sharp words to be exchanged between them, Raph regretting it every time he stalked off to cool his head down.

It got to the point that Don couldn't take any of his brothers' pesterings any more and after a simple question of "are you feeling okay, Donnie?" from Mikey at dinner that he finally snapped and screamed at them he was fine, why couldn't they leave him the shell alone, could they not see that's what he wanted, they were stressing him out more and more with their inane interrogations, before ending his rant and stalking out the door with the statement he was going topside for some breathing room and peace and quiet.

He left the lair at a run, jumping through the first manhole cover he came across up onto the street and sprinting for the nearest building, years of ingrained instructions to never be seen driving him before anyone did. He was up to the roof in a heartbeat and running swiftly with practiced ease over any obstacle that stood in his way, twisting, turning and switching directions randomly.

Don eventually stopped on one of the rooftops quite a ways from the lair, doubled over and out of breath. He looked over his shoulder as he heaved great gulps of air. No one followed him. Good. He shuffled to a wall strut and leaned his shell against it, and then slid down until he was sat on the ground. As his breathing finally slowed he lifted his hands and flexed his fingers, staring at them, studying them.

He was the only one not of their blood, he was the odd turtle out. Why did it bother him so much? Leo told him he would always be their brother no matter what, and Don believed him. It was not like the last sixteen years would suddenly vanish simply because he wasn't a blood relative.

And it made _sense_ in Don's head. He had never been the strongest turtle, most often the first to fall in a fight. He was smarter than all his brothers put together and then some, something he was positive they resented him a bit for. He was leaner, more flexible than any of them, had a much faster thought train, the tallest out of their not-so-tall heights, the most easily distracted...

The list went on.

Really, it shouldn't matter. It's not like Leo, Raph and Mikey weren't different. They pretty much re-wrote an extreme end of the personality scale each, himself included. Obssessive compulsion often won with him.

And yet it did. Somehow, some way, it did. Knowing he wasn't blood, knowing now why he didn't seem to be quite on the same wavelength, knowing he couldn't share, study or research the supposed intuative links between siblings... It buckled him on the inside, warping a fear he'd carried for most of his life, it seemed. A fear of rejection by his supposed siblings, a fear he'd never fit with them, a fear they'd never care for him the way he cared for them.

As though by confirming his non-relation status it had made those fears a reality and he couldn't face them. He clenched his fists, stood up, narrowed honey-brown eyes, and then screamed. He keened long and hard into the shadowed night sky, eventually stuttering off and dropping to his knees as they refused to support him anymore. The young turtle curled in on himself, wrapping his arms around his torso and closing his eyes, tears pricking at the edges of them.

-x-

God knew how long he stayed like that, curled up with tears running down his cheeks, and frankly he didn't care. He only looked up with he heard a footstep from the same rooftop he was currently calling his reside. Honey eyes narrowed, and he dared to finally move and peer out briefly to see who, exactly, thought they could interrupt his rather Raph-like brooding and emotional breakdown and get away with it.

His annoyance turned to surprise when he saw Leonardo straightening from obviously having jumped to the roof. He stood up slowly, glowering when Leo saw him and smiled.

"How did you find me?" There was no warmth to Don's voice, which made the blue-banded turtle's smile falter. "I said I wanted to be alone."

"That was three hours ago," replied Leo quietly. Three hours, huh? Don was impressed with himself at the amount of brooding he could apparently put in. "I came to find you, make sure you were okay."

"I don't need you mother-henning me!" Don snarled. "You always do that, and it's irking the shell out of me right now."

"I'm only worried, Donnie. Please, talk to me. You know you can tell me anything."

Don started to feel anger seeping through his body, and he straightened. "There's nothing to talk about, Leo."

"Yes, there is. Something has been eating at you, and I want to know what it is. Let me help you, Don!"

An illogical fear suddenly welled up in Don as Leo started walking steadily forwards, arms out slightly in submissive gesture, and that scared him even more. Don made an odd noise and backed up to a demolished chimney. Eyes hazed slightly as Leo continued moving.

"No! Leave me alone!" Don threw a broken piece of rubble at the turtle advancing slowly and placatingly towards him. "Why do you care, I'm not your brother!"

"But you are, Donnie," said Leo, raising his hands in surrender after dodging the projectile but not stopping his forward movement. "C'mon bro, we love you and care about you, and we want you home."

A derisive snort, wild honey-hazel eyes glazed slightly in scared fury and unfocussed. "Yeah right. You've always been jealous of me, admit it! I've always been jealous of you! The way you can act around everyone, shred all embarrassment and uncomfortable wariness when around them, how good you are at your training? I want to do that! Instead I'm a closet recluse, I'm people-shy and all I'm good at are electronics and machines!"

"That's not true." It was spoken softly but firmly, making a point without sounding accusing. "You're the level head that keeps us together, Don. You're the one we can count on to get us out of a spot, you're the one with the intuition and creativity we could never match, you're the one with the most to lose." Leo extended his arms forward. "Come home, Donnie, please. We need you, brother. We need you."

"So you are jealous." Don gripped his bo staff, debating whether to attack the turtle in front of him or find some way to shake him. Apparently his violent streak decided to surface, and he sprinted towards Leo wildly, staff in tow.

Leo blocked the incoming swipe as best he could (since when the shell did Donnie get this fast?) and dodged the next one meant to hit the backs of his knees. He pointedly refused to draw a katana though, never wishing to go as far as to pull out a weapon on his own brother. Not when he was in this state, anyway; Don just wasn't in his right mind.

The fact that he refused to use his weapons apparently only vexed Don further, and the attempts got more brutal and harder to keep track of.

"I know you talk about me!" Don yelled as he flew past Leo thanks to a counter, and he was up and racing back once more as though it hadn't phased him. Leo knew he'd landed hard, that _must_ have hurt somehow. "Behind my back, talking talking, always talking. Bad, rude, not right. Don't think I haven't heard!"

"Heard what, Don?" Leo fought to keep his voice neutral, stop the anxiety, worry and slowly seeping anger sliding into it. "We call you a genius, a marvel, graceful, patient, creative. We call you brother."

"Liar!" Don's voice broke as he flailed blindly at those words. "Liar, liar!"

"No, Donnie. It's not a lie and you know it."

Blocking, ducking, dodging and trying to calm his hysterical sibling all at the same time meant Leo didn't hear or see the shadows that descended on them before it was too late, because until that point Don had been his entire focus and world.

The purple-banded turtle noticed their new arrivals at pretty much the time Leo did, and the attacks on said katana-whielder ceased immediately in favour of turning all his pent-up rage, frustration and confusion against the Foot instead. It was at this point Leo finally drew his blades and stepped back in line with his brother, glowering at the Foot surrounding them. He wondered if anyone had ever told them that they were absolutely crap at their timing.

He felt tired after evading the neurotically tempestuous storm of a turtle next to him, but Don himself looked thoroughly exhausted through the tumultuous emotions scrawled all over his features. He had completely drained himself doing all the work going after his brother, and seemed now to be running on nothing but pure adrenaline. His eyes were dulled but wary, angry, accusing.

It was all the Foot's fault now.

Letting loose a wild cry that would've made Mikey proud, Don launched himself right into the middle of the ninja and was immediately taking them down. One by one, mercilessly, chaotically, they fell to the bo staff. Not sharp cutting blades like Leo or Raph's weapons, but still just as deadly. As a lot of the Foot were now apparently remembering.

Leo tried to reach his brother to keep an eye on him and help him, but his own personal pack of attacking ninja seemed intent on refusing him that right. There was no way they were going to let him near Don, and no way Leo was letting them stop him. So he fought.

However worn out as they were it began to take a toll, and after a while there was a sharp cry of pain from Donatello, and then a shriek as whoever had hurt him got a bo to the face. During that time another Foot got in and slashed his sword right down Don's plastron, earning another grunt of pain and then adding to the body count. A third took advantage of an opening caused by the pain from both the huge gashes now decorating a shoulder and his plastron, and added another on his side to the collection.

Don was getting slaughtered as his adrenaline wore off, and wasn't going to last much longer if Leo didn't do something about it.

-x-

Don couldn't help the scream that tore from his lips as a sword went straight through the top of his shoulder, but the pain was quickly dulled and he turned on the Foot goon with a vicious swipe that cracked him on the temple. A small spray of blood erupted from the point of impact, causing a hint of a smirk from the purple-banded turtle. He hoped it had cracked his skull.

Taking advantage of Don's momentary distraction there was another warm slice that burned its way down his plastron, making him sound out in surprise, and his icy honey gaze turned to a Foot ninja in front of him, bloody sword poised in front of him. The bo staff raised and the next second that Foot had a broken jaw, several broken ribs and cracked kneecaps.

As he brought himself around to face his next opponent, he was sent to the turtle in the form of a speedy, flying assailant who managed to slice his side open before the bo staff followed him and smashed the back of his head in.

Everywhere he turned Don was getting more and more injuries, the fatigue starting to show through even the adrenal rush streaking through his veins. His mind wouldn't stop swirling, whirling, fading in and out, making itself dizzy so the genius could think. He was having to resort to pure instinct, something he hated doing.

He was so focussed on the Foot ninja before him, fury making him random, faster, vicious and deadly towards them, that he failed to notice the form that crept up behind him until there was a blade from a double-ended katana sticking through his chest, skewering him from behind.

As of all the adrenaline rushed out of him in one go through that act he gasped, eyes widening before he dropped his staff and fell to his knees for the second time that night as the blade withdrew. A hacking cough brought up blood to his hand, which he stared at in growing horror.

And it was that horror and the thought that he could very well die like this that suddenly quelled the unrestrained, hysterical vortex his mind had been swirling in, and his mind became sharp and clear as the veil of emotion was pierced thoroughly in just a few seconds.

He watched Leo's face drop into terror as he realized what had happened, and as it changed into pure, unadulterated rage Don wondered how on earth he could have thought that Leo didn't care for him. He raised his hand and stared at it, the red glistening beautifully against his skin's olive-green hue. Just because they didn't share blood. Just because he'd been selfish, just because he refused to believe, just because he couldn't handle the fears he should have been able to defeat.

Leo fought and fought against the waves of Foot trying to reach Don, and the bojutsu learner tried to tell him to stop and get away or he'd be killed and he would never forgive himself or Leo if that happened, but all that came out was another coughing fit and another spout of blood. He pulled his hand away from his chest, and whimpered as more of the precious red liquid spurted from the wound. _Keep pressure on it. Find something to wrap it in. For God's sake, don't lose any more blood!_

He noticed one of the Foot ninja he'd downed earlier was right near him with a torn shirt. He could use that, couldn't he? Keeping his palm pressed tightly to the gash Don fell forwards onto his other hand and began crawling slowly, gingerly to the body.

He reached it, exhausted, but managed to dredge up enough reserve energy from somewhere to rip the shirt off the Foot and start attempting to bandage himself. He got it around himself once, but it wasn't tight and it certainly wouldn't stop the bleeding. His head started spinning again and his breathing became more laboured and deeper, signs he recognized as severe blood-loss. If he didn't do something soon...

A crash right next to him made him jump, and Don peered through his haze to see Leo grimacing in pain and holding his arm, down the length of which was an extremely deep laceration. Blood was flowing fast and freely from it, and Don guessed an artery or vein had been caught. Leo tried to get up again, but a whimper from Don stopped him.

The enraged visage morphed to worry and alarm when the blue-banded turtle saw just how bloodied his brother was.

"Don..."

"Leo, don't," Don rasped, finally managing to force some words past his lips. "Please, go. Save yourself, don't worry about me."

"Don't say that!" Leo snapped, his fright finally fully showing through. "Dammit Don, stay with me!"

"Go..." Don squeezed his eyes shut as another fit of coughs racked his body, leaving him shivering and unable to say anything else.

"Just stay with me bro, I'll get us out of this. I promise!"

Don was about to try and speak once more when something behind Leo caught his gaze, and a small smile graced his face for the first time in a few days. Shaky, tiny, but it was there. Honey-brown eyes glazed over slightly, and Leo risked a look over his shoulder.

And he couldn't help a slightly hysterical laugh of relief. Michelangelo whooped as he landed heavily on top of three Foot, downing them in one shot before cutting paths swiftly through the troops. Raphael was furious, taking out every Foot he came across mercilessly and surprisingly efficiently. Master Splinter too was joining in, protecting his sons with everything he had. It crossed Leo's mind that he looked younger fighting here than he had done in years, not since they were tots.

He slumped down, trusting his family to take care of them. He had a younger brother to look after himself. Don's eyes were fluttering fitfully, wanting to close but Leo could tell he was fighting it.

He began talking hoarsely about everything and anything, ignoring the pain signals from the wound on his arm that was creating a small puddle of red under him, hoping that Don would focus on his voice. Just focus and keep awake.

Apparently to no avail, thought Don as he found he was quickly losing the battle. He tried desperately to keep Leo's voice in the forefront of his mind, clinging to it like a lifeline, but the tugging of oblivion was getting stronger and stronger and Don's grip was getting weaker and weaker.

He'd lost too much blood.

He felt the older turtle gather him up in an embrace, tears in his voice now pleading him not to go. Don felt his own cheeks dampen with something other than blood, and his eyes drooped. The last thing Don saw before unconsciousness took him away was his and Leo's blood pooling around them both, mingling and swirling together in patterns of every red you could imagine, and his last conscious thought was _'it's the same as mine... I am his brother.'_


	2. Too Little, Too Late

"Please Donnie, don't do this t' us! C'mon bro, stay with me, stay with me!" Raphael desperately changed the pad he was trying to stem the blood flow with and continued attempting to close up the artery that Elite's blade he pierced. He wasn't having much luck, and Don was losing too much blood too fast. His hands started to tremble as they slipped off the needle he was using again, trying to ignore the sight of two broken plastron halves either side of him, shattered from the Elite's attack.

"We're going to need to get some more blood into him, even I know that's way too much lost," said Leonardo, pressing down on the pad Raph had exchanged and feeling with some nausea the warm red liquid swelling up and soaking the towel and his fingers.

"I know, I know!" snarled Raph, shaking his head to snap himself back to attention. "Masta Splinter!"

Their sensei looked over from where he was sat comforting Michelangelo, who was far paler than should be healthy and shaking like a leaf. "Yes, my son?"

"Go get our DNA chart thingies 'n tell me if one of us matches Don's blood type. He needs some 'n fast." Raph's eyes narrowed as he finally managed to seal the artery somewhat so it wasn't spurting blood all over the place anymore. "That should slow it. Leo, keep the pressure on."

"I'm glad Donnie taught these things to one of us," breathed the blue-clad turtle.

"He tried t' teach both o' yas too, but ya were too busy focussin' on trainin' 'n Mikey was way too fidgety," Raph accused sharply, golden eyes boring into his elder brother's.

Leo was about to retort when Splinter came back with Raph's sheet. "Raphael, it seems you are the only one with the B+ blood that Donatello needs," he said quietly before going back to Mikey. Raph nodded.

"Leo," he said, gingerly picking up a big hypodermic needle and attaching it to a piece of machinery underneath the surgical trolley, "find the vein in my arm and get the needle in."

"What?" Leo looked startled. "I can't do that!"

"Ya can 'n ya will!" Raph took over applying the pressure to Don's wound and thrust the needle at Leo. "It's either yeh try or he dies. Do yeh want Don t' die?"

"No, but..." Leo looked queasy as he took Raphael's arm and poked gently at it in an attempt to find a vein. He found one surprisingly easily, but then discovered that actually spiking the vein was another matter entirely. Seven tries later he finally got the needle in, and Raph very quickly pushed the other needle sticking out on the machine sat quietly beeping to monitor Don's vitals into Don's arm as Leo took over pressure duty once more.

A button, switch-flick and two seconds later, and blood was drawn up from Raph's arm into the machine and then cycled into the olive turtle unconscious on the table. The red-banded turtle went back to sorting out the rest of the internal wounds he could find, stitching up what needed stitching and realigning what needed put back properly.

About an hour went by before Raph decided that three pints of blood, a lot of shivering and dizziness on his part and what seemed to be a stable brother were good enough reasons to end the surgery and clean up. The heart monitor beeped steadily at them all, reassuring them that yes, their genius brother was still with them.

Raphael just about collapsed into Leo afterwards, who wordlessly wrapped a blanket around the turtle and disappeared briefly to get him some food and a warm drink. Leo then led his younger sibling over to a still-pale and shocked Mikey and a silent Master Splinter, and the four of them huddled together to wait and see.

-x-

It wasn't until early the next morning that something happened, but it wasn't at all what they were all hoping for. The heart monitor suddenly started going crazy, waking a cursing Raph who had been sleeping on Don's couch - the same one the purple-banded turtle used if he had been up late into the night working and was too tired to get to bed.

Donatello was arching up from the table, clearly in pain and gasping for breath. Raphael hollered for Leo as he tried to hold his younger brother down, noting with a sinking feeling in his gut that the clean bandages he'd put on the previous evening were thoroughly soaked in blood. The katana-wielder screeched into the room, following Raph's instructions to try hold Don down without question as the sai-master grabbed some scissors, snipped the stained cloth off and pulled apart the broken plastron again.

"No no no no no no no! Donnie c'mon, don't do this!" Raphael paled as realized either his stitching on the pierced artery must have come undone or he had missed something, because there was about as much blood outside the wound as there was inside the cavity Raph had been working in when he cut the external stitches and opened it up again. "He's bleeding from somewhere, but I can't tell where; there's too much blood!"

"Can we do another transfusion?" asked Leo hurriedly, panic rising pretty rapidly through his system.

"Not this early after one. There's no way I'd be able to give any more blood and survive." Raph gritted his teeth and ordered Leo to hold on tighter before diving back into the wound again to try and find and stop the leak.

-x-

There were no expressions of triumph or celebrations as Raphael and Leonardo slowly left Donatello's lab, only ones of shock, dawning horror and threatening waves of tears. Their second-youngest sibling, their genius brother, the glue that held them together, was gone.

Dead.

Forever.

Raphael looked down at his blood-soaked hands, unable to wash them clean despite the fact he hated the sight of them now.

He had failed.

He had failed Donnie, he had failed his family and he had failed in saving a life. When it mattered most, he couldn't deliver.

So he collapsed to his knees and screamed. He screamed his heart out until his voice broke, and didn't need to hear Mikey's cry of, "No!" or Splinter's muffled sobs to know that they knew.

A weight fell on top of him, holding him, embracing him, offering an empty comfort. Leo was crying too, his tears falling onto and tracking down Raph's shoulder. The sai-wielder clung to his older brother, too overwhelmed to do anything else. Tears blurred his golden eyes, and he squeezed them shut in the hopes that this was all some very, _very_ bad nightmare and he was going to wake up and find that he'd crawled into Leo's bedroom at some point and Mikey would be laughing his shell off at them both and Donnie would be in the kitchen waiting for them all with a big grin and breakfast ready.

Only when he opened his eyes again things were exactly the same as when he'd shut them, reality distorted as it couldn't, wouldn't sink into them that Don was...

Raph couldn't bring himself to finish the statement.

He refused to let go of Leo even as the older turtle finally rose and ushered them all out into the kitchen to make some tea, pride be damned. He was in too much pain to care.

How odd it was, though. Raph never really cared about physical pain, he could handle that no problem. Yell at Leo, throw a couple things around and a twenty-minute whinging session with Don trying to patch him up always worked, and it never bothered him after that. But this... this was completely different. This wasn't a physical pain, this wasn't an easy fix. It was never going to leave, it would always be in the back of his mind. And he was completely lost as to what he should do.

So he did the only thing he could; he clung to his brother like his life depended on it, despite the fact he knew that Leo was in just as much pain as he was. Leo always knew what to do.

-x-

"Feeling any better?"

Raph started and looked up to meet the concerned gaze of Leonardo, steaming cup of herbal tea in the blue-banded turtle's hand which he passed to the sai-user. Raph shook his head but accepted the drink with no-longer red hands.

"How's Mikey?" he asked hoarsely, dodging the question.

"Exhausted. Sleeping. Completely torn-up. In shock." Leo paused. "How are you feeling, Raph?"

Raph slowly swirled the cup's contents around as his brother sat next to him, and didn't object to the arm that embraced his shoulders comfortingly. "It was my fault," he said quietly. "I didn't spot he had another cut that could rupture at any time. I wasn't thorough enough, I failed."

"No, Raphie." Leo pulled Raph's head round to face him gently. "It wasn't your fault, you did everything you could and more. I looked it up; you should've passed out after giving away three pints of blood, but you kept going because you were determined. Donnie would be proud of you, just like me."

"How can you be proud of me? I killed our brother!" Raph stared at him angrily, incredulously.

"No, you didn't. The Foot did, and they're going to pay for this." Leo sighed and closed his eyes, but Raph could see the pricks of tears gleaming at their edges. "You did everything you could, you gave everything you had and managed to stay alert and standing long after any of us would've collapsed and given up. And I'm proud of you for that. We don't blame you, Raph, so don't blame yourself."

"I-" Raph was cut off as Leo went from an arm around the shoulders to an all-out hug, clinging tightly to the red-banded turtle.

"Please. Please don't, Raphie. It wasn't your fault, so please don't take the blame!"

Raphael was so startled by his brother's voice cracking that badly and the embrace, even though he knew his brother wasn't the touchy-feely type, that he found himself promising before his brain caught up with his mouth.

And yet somehow, that felt right. He could be to blame for not spotting the other rupture in Don's body, but he wasn't at fault for Don's death.

No, the Foot would pay, just as Leo said. They would pay, very painfully and brutally if he had his way. And then, Raph thought as Mikey slipped quietly to them and snuggled between his brothers, it would be okay. They would be okay. They could get through this together, they could deal.

Donatello was still with them, even if it wasn't physically, and always would be. Just like Master Splinter's sensei, the one whom he considered his father-figure. Raph briefly wondered if they'd met wherever they were, and whether Yoshi would be able to handle the boundless curiosity that was Don. The thought brought a sad smile to his face as he ran his fingers gently over a sleeping Mikey's shoulders and shell, tangling and untangling the orange bandana tails as he did.

Raphael looked up as Splinter came into the room to see his sons curled up together, each taking comfort in the others' presence, and his face twisted in anguish again and he buried his face into Leo's plastron. Splinter walked over and placed a hand lightly on Raph's arm, sitting next to them in silence but letting them know that he was there and he too was hurting as much as they.

-x-

That night, Raphael Hamato prayed. For the first time in his life, he prayed. He didn't know why, it just felt like the right thing to do. So that's what he did.

And as he finished he fancied he could hear a light, smooth laugh reverberating around his room, a laugh that could only belong to one person.

"Oh quit yer giggling, Donnie," he grumbled. "I'm gonna kick your shell when I see you again for that, I swear."

His only answer was silence, but somehow he was satisfied Don had heard him.

And with that, Raphael got into bed and drew the covers up and over his head, cocooning himself and hoping he could get at least a couple hours' sleep in before they started trying to pick up the pieces of their lives tomorrow.

_Goodnight, Raphie. Thank you._

* * *

**Rae:** I told you! Can't say I didn't warn you! Ö The bunny refused to be written any other way. It was the fact I had to kill _Donnie_ that was the hard part. The writing was easy. (sniffles)

Umm... review, and please don't kill me? (cringes)


	3. Alt Ending: Precious

**Rae:** Because it was a very ambiguous bunny and I couldn't leave Donnie dead. I just couldn't! D:

* * *

Don awoke very slowly to a swirling mass of silvers, whites and creams, something he recognized vaguely in the back of an extremely out-of-synch brain. He scrunched up his beak at it, trying to work out what it was and dampen down on his obviously drug-induced haze.

Nothing else could screw him over like this.

He suddenly managed to place the thing still mixing itself up in front of him. The ceiling. In his lab. Which must mean...

Don gingerly hauled himself upright and looked around, squinting through adjusting eyes. Yep, it was his lab alright. The medical part of it. Everything was in place except his surgical trolley, which was sat right next to his bed instead of near the workbenches and piled high in bloody bandages and pads to the point that they are drenched, scissors that had once been a sterile silver and were now a dark, foreboding red, a needle he noticed was for wound stitches that still had a used silken thread dangling from it, a used hypodermic syringe which was only for anaesthetics and several jars and pots of various medicinal chemicals.

He wondered for a moment just who was injured that badly and why was he in bed when he should be treating them. And then his last memories came flooding back to him. His guilty trip out, Leo finding him, facing off against those all those Foot idiots, getting stabbed...

A hand flew to his chest with a gasp, flinching as a flare of pain shot through him. Leo. Wait, Leo! He got hurt too. Where was he? A glance round showed he wasn't in the medical lab. Maybe he was outside, then.

The purple-clad turtle shifted carefully to the side of the bed, where he swung his legs over and stood up very shakily. A sudden metallic rattle next to him caused him to sit back down abruptly in surprise, and he was a little intrigued to discover he was attached to an IV frame which was feeding him blood from a bag marked 'B+' roughly in black marker through a catheter in his arm. He poked at it a couple times.

Huh.

_Who has the same blood type as me? _wondered Don as he scrambled to his feet once more. Oh whatever, he'd found out soon enough. First things first. Leo. He gripped the IV frame for support and shuffled towards his lab door with it creaking and spindling along next to him. He felt weak, cold, unhealthy.

He hated it.

He hated it even more when he got to the door and found he was out of breath and exerting every muscle to its fullest just to keep his grip on the frame and stay upright. The lab doors hissed quietly open, and honey eyes were immediately shielded against the onslaught of bright white light compared to the soft, low gleams in the lab.

_Leo..._

Don opened his mouth. And then closed it. Would his voice work this time? He massaged his throat once, twice. And tried again.

"Leo?"

It was hoarse, raspy and strained, but it was there. "Leo?"

A rustling sound, and then someone ran up to him with a surprised noise. What little strength Don had finally gave out at that moment, but he was caught before he hit the floor.

"Christ Don, what the shell d'ya think yer doin'?" Raph muttered, guiding a weakly-protesting bojutsu master back to his bed. "Ya ain't ready for walkin' yet."

Don gripped Raph's arm, making the red-banded brother's golden eyes snap to his. "Raph, where's Leo? He okay? What happened?"

"Slow down, Brainiac." Raph checked Don's IV, poured a glass of water and handed it to his brother, and then sat down on the side of the bed. "Leo's fine. A bit weary, but fine. You, on the other hand..."

Don took a grateful drought of the clear liquid, feeling the effects immediately as his head cleared a bit more and his throat felt better. He put a comforting hand on Raph's arm, placating, questioning.

"We actually lost ya there for a while. How I managed t' get ya back-" Raph's eyes closed. "I told Masta Spinter t' go check our DNA charts as soon as we got ya back here and see if any of us were compatible blood types with ya. Turns out I was." The sai user opened gold orbs and nodded to the blood bag. "'S all mine, that."

The bo-staff wielder looked fairly horrified that Raph had to be the one performing all the 'doctor crap' as he so judiciously called it, but somewhere in his mind the bojutsu turtle was also extremely relieved he'd managed to pass his knowledge to one of his brothers for this exact reason.

"Scariest time of my life." Raph buried his face in his hands. "I fergot everythin' ya taught me, Donnie. Went straight out my head and it wasn't until Mikey slapped me 'n told me t' get my tail in gear that I acted. It was..." He paused, thinking of the right word. "...instinctive."

"Raph." His name was enough to get his attention, bringing his face from his palms to look at Don. "Thank you. And... I'm sorry."

"Just don't ever do anythin' that stupid again." Raph studied Don up and down, and then dropped Don's hand in favour of standing up and facing him, fists resting on his hips. "Donnie, lookit me. Tell me what ya see."

"I see..." The bo staff wielder looked uncertain. "I see you. I see a mutant ninja turtle. I see a shell, six fingers, four toes and your favourite color."

A hint of a smirk flashed across Raph's lips. "Now lookit yaself and tell me what ya see."

Don realized exactly what Raphael was getting at then, and tears pricked at the corners of his eyes. _I'm the same as him, he's the same as me. Why, oh WHY was I so idiotic about all of this?_ "I'm so sorry Raphie, I should never have thought you guys didn't care. I just... something about that whole thing set off my deepest fears and brought them to the surface, and I lost all control of myself."

Raph didn't say another word, just allowed the olive turtle to hug him desperately and get it all out of his system, and then laid him gently back down on the bed as Don fell asleep again soon after from wearing himself out physically and emotionally. He contemplated the sleeping turtle next to him for a few minutes, fingering the bloodied bandana tails drooping despondently off the edge of the surgical trolley, and recognized just how much he and the others actually took Don for granted.

Everything he did they relied on him for it, and it had become too much of a second-nature thing.

Raphael knew that if he needed to vent things Don would always have a willing ear and an unsubjective view, giving good advice and quiet support. But who did that for Don?

Michelangelo relied on his geekery to fix the broken electronics around the lair, from his gaming consoles to the toaster. But who stopped those interruptions on Don's days off and have somone else do it for a change?

Leonardo always made sure Don kept the lair's security up-to-date and suggested improvements, just so he could keep the family safe. But who made sure Don was looking after himself properly and keeping himself safe?

They would never take Don for granted again, Raph decided, as he heard the doors to the lab open. He looked up and cocked a small but genuine grin at the two turtles who entered and each sat themselves silently around their injured brother. Leo took one of Don's hands in his own and massaged the back of it comfortingly. Mikey rested his head on Don's chest, under the wounds so he wouldn't aggravate them, and closed his dimmed blue eyes. Raph just took in the scene for a moment and then locked eyes with Leonardo, who was watching him steadily.

Donatello would always be their most precious brother, blood or not.


End file.
